Paper ID #26007 The Logic of Decision Making in Engineering Design: An Examination of De- sign Theories From A Logical Point of View Dr. Soheil Fatehiboroujeni, Indiana-Purdue University Soheil FatehiBoroujeni received his Ph.D. in Mechanical Engineering from the University of California, Merced in 2018. As a postdoctoral researcher at Purdue University, School of Engineering Education, Soheil is working on a multi-institutional project characterizing governance processes related to change in engineering education, and pursuing other research interests in epistemology and design, among other philosophical topics in engineering education. Dr. Donna M. Riley, Purdue University-Main Campus, West Lafayette (College of Engineering) Donna Riley is Kamyar Haghighi Head of the School of Engineering Education and Professor of Engi- neering Education at Purdue University. c American Society for Engineering Education, 2019 The Logic of Decision Making In Engineering Design: An Examination of Design Theories From A Logical Point of View Abstract Designers rely on a variety of objects, practices, norms, and domain-specific knowledge when con- fronting the design tasks and undertaking their professional responsibilities. The responsibilities of individuals or groups (i.e., specific tasks at each stage of the design process) in their terminal phase, form a set of decisions that need to be negotiated horizontally, i.e., across teams, domains, and disciplines, as well as vertically, i.e., across hierarchical chains of authority that institute the design process. Therefore, a theory of justification and rationality of decision making in design has to account for the intersubjective or social nature of design. In negotiations, a diversity of con- straints, commitments, and priorities clash, yet resolutions are found by some type of justification or rationalization. Design researchers and methodologists have developed or adopted theories of rational decision making, all with an impetus to enhance the efficacy of this process. While in meta-theoretical debates in human sciences or philosophy, the notion of logic is itself examined and debated, the majority of design methodologies take the meaning of logic as a given foundation or self-evident core of truth, traceable to what is often called classical logic. In this paper, a number of design methodologies are briefly reviewed and three categories are in- troduced based on the logical commitments of methodologies. The first category entails methods such as rational choice theory that first developed within the discipline of economics and are built upon ternary axioms of classical logic. The second type of methods which have found application in the world of design to a lesser extent are built upon probabilistic or multi-valued logic. And finally, the third category encompasses theories of decision making built upon a dialectic interpre- tation of logic which we propose as a viable alternative for engineering design. decision making in the literature of social and political sciences has been continuously a focus of scholarly attention. Models and frameworks in this space often take into account the complex socio-political context of decision making and ensuing strategic action. We discuss the elemental role of epistemology and ontology in both theory and practice of design considering the socio-historical character of rationality, negotiations, and justification in engineering. In addition, we present how formal dis- putations as the most prominent instance of dialectic processes can provide a framework to map the reasoning and thinking in design by using a preliminary data analysis. Keywords: logic of design, decision making, design philosophy 1 Introduction Design and engineering of technological artifacts are the core functions of modern corporations that are situated in an increasingly international network of production, distribution, and exchange. It is well established in Science and Technology Studies (STS)1 or history and philosophy of tech- nology2,3 that social and political intentions as well as technical and instrumental necessities deter- mine the outcome of design and engineering decisions. Industrial and technological corporations are establishments with financial, political, and moral roadmaps that among other entities such as research universities, national labs, or government agencies constitute an ecology of knowledge4. Contemporary and historical accounts of this ecosystem demonstrate how rearrangements in the national priorities, aspirations, and changes in domestic or international landscape of politics and economics contribute to the evolution and production of knowledge. Therefore, in design research a fundamental epistemological question is the relationship between the individual and the social levels of analysis. Do the individual factors such as cognitive models used by designers explain the phenomenon in question, or do the social factors such as institutional and legal frameworks, and more importantly historically accumulated forms of cultural and material capital buttress epistemic explanations of the individual actions? Moreover, even if one confers the epistemic status of objectivity or observer-independency to the knowledge of technical and scientific disciplines, any application of these forms of knowledge for synthesis of technological artifacts involves perspective taking, boundary drawing, and premedi- tated human action, therefore problematically subjective, i.e., conditioned by observer-dependent factors such as (tentative) judgements, calculations of interests, and even individual or group sen- sibilities. With design, one intends to change the world (or parts of it) and changing the world or working for the betterment of any state of affairs, presupposes an interpretation or a conception of the world. The world can not be designed from without, but from within. Here, we are interested in engaging with the theoretical implications of such a self-reflexive process. This paper seeks to analyze how design researchers resolve the relationship between objective contexts and structures, versus the subjective agency and intentionality of designers. The basic and long-standing questions we touched upon in that past two paragraphs–first the rela- tionship between the individual and the social direction of explanations, and second the relation- ship between the structure and agency–are at once epistemological and ontological. Any inquiry seeking to systematize or resolve these questions would entail knowledge claims (interpretations and/or explanations) on the characteristics and constitution (nature) of engineering design. This paper is an effort to demonstrate how a logical point of view, i.e., examining how inquiries in de- sign research figure the notion of logic, can make effective inroads in addressing aforementioned questions. Design researchers and methodologists have developed or adopted various theories of rationality in engineering decision making, all with an impetus to enhance the efficacy of this process and often to bring to light the essence of design. In this paper, a number of design methodologies are briefly reviewed and three distinct categories are introduced based on their logical commitments. The first category entails methods such as rational choice theory that first developed within the discipline of economics and are built upon ternary axioms of classical logic. The second type of methods which are yet less applied in the world of design are built upon probabilistic or multi- valued logic. And finally, the third category encompasses theories of decision making built upon a dialectic interpretation of logic which we propose as an alternative. decision making in the literature of social and political sciences have been continuously a focus of scholarly attention. Models and frameworks in this space often take into account the complex socio-political context of decision making and ensuing strategic action. We discuss the elemental role of epistemology and ontology in both theory and practice of design to better make explicit the socio-historical character of rationality or justification in engineering. In addition, we present how formal disputations as the most prominent instance of dialectic processes5 can provide a viable framework for mapping the reasoning and thinking in design. 2 Logic of Design In western philosophical tradition logic is concerned with examining the structure of valid infer- ences. For example, a syllogism, or a deductive argument each have a unique underlying logical form or structure. Form in this context refers to the relationship between context-independent logical terms such as and, or, if and context-dependent terms such as woman, gene, machine6. A logically true inference, in this tradition, is true by virtue of its form regardless of the content. Logical forms, hence, are relational patterns of locutions (verbal elements) in statements. Logic, thus construed, is the science of necessary thinking7 or necessary inferences6. Ever since the inception of this tradition, several problems have arisen as the framework has ex- panded. Examples include inferences regarding time (past, present, future) or events influenced by human action (e.g., a battle or a contest) that create a theoretical impasse, commonly known as the “problem of future contingents”. Another long-standing, consequential, and actively researched problem is that of semantics, i.e. the relationship between the meaningful and true statements and the reality to which statements